/**
 *    Copyright 2009-2018 the original author or authors.
 *
 *    Licensed under the Apache License, Version 2.0 (the "License");
 *    you may not use this file except in compliance with the License.
 *    You may obtain a copy of the License at
 *
 *       http://www.apache.org/licenses/LICENSE-2.0
 *
 *    Unless required by applicable law or agreed to in writing, software
 *    distributed under the License is distributed on an "AS IS" BASIS,
 *    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *    See the License for the specific language governing permissions and
 *    limitations under the License.
 */
package com.yinsin.jpabatis.logger.jdbc;

import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Method;
import java.lang.reflect.Proxy;
import java.sql.CallableStatement;
import java.sql.PreparedStatement;
import java.sql.ResultSet;

import org.slf4j.Logger;

import com.yinsin.jpabatis.reflection.ExceptionUtil;

/**
 * PreparedStatement proxy to add logging
 * 
 * @author Clinton Begin
 * @author Eduardo Macarron
 * 
 */
public final class PreparedStatementLogger extends BaseJdbcLogger implements InvocationHandler {

	private final PreparedStatement statement;

	private PreparedStatementLogger(PreparedStatement stmt, Logger statementLog, int queryStack) {
		super(statementLog, queryStack);
		this.statement = stmt;
	}

	@Override
	public Object invoke(Object proxy, Method method, Object[] params) throws Throwable {
		try {
			if (Object.class.equals(method.getDeclaringClass())) {
				return method.invoke(this, params);
			}
			if (EXECUTE_METHODS.contains(method.getName())) {
				if (isDebugEnabled()) {
					debug("Parameters: " + getParameterValueString(), true);
				}
				clearColumnInfo();
				if ("executeQuery".equals(method.getName())) {
					ResultSet rs = (ResultSet) method.invoke(statement, params);
					return rs == null ? null : ResultSetLogger.newInstance(rs, statementLog, queryStack);
				} else {
					return method.invoke(statement, params);
				}
			} else if (SET_METHODS.contains(method.getName())) {
				if ("setNull".equals(method.getName())) {
					setColumn(params[0], null);
				} else {
					setColumn(params[0], params[1]);
				}
				return method.invoke(statement, params);
			} else if ("getResultSet".equals(method.getName())) {
				ResultSet rs = (ResultSet) method.invoke(statement, params);
				return rs == null ? null : ResultSetLogger.newInstance(rs, statementLog, queryStack);
			} else if ("getUpdateCount".equals(method.getName())) {
				int updateCount = (Integer) method.invoke(statement, params);
				if (updateCount != -1) {
					debug("   Updates: " + updateCount, false);
				}
				return updateCount;
			} else {
				return method.invoke(statement, params);
			}
		} catch (Throwable t) {
			throw ExceptionUtil.unwrapThrowable(t);
		}
	}

	/**
	 * Creates a logging version of a PreparedStatement
	 *
	 * @param stmt
	 *            - the statement
	 * @param statementLog
	 *            - the statement log
	 * @param queryStack
	 *            - the query stack
	 * @return - the proxy
	 */
	public static PreparedStatement newInstance(PreparedStatement stmt, Logger statementLog, int queryStack) {
		InvocationHandler handler = new PreparedStatementLogger(stmt, statementLog, queryStack);
		ClassLoader cl = PreparedStatement.class.getClassLoader();
		return (PreparedStatement) Proxy.newProxyInstance(cl, new Class[] { PreparedStatement.class, CallableStatement.class }, handler);
	}

	/**
	 * Return the wrapped prepared statement
	 *
	 * @return the PreparedStatement
	 */
	public PreparedStatement getPreparedStatement() {
		return statement;
	}

}
